Stephen was a Cappadocian who became a monk under Patriarch Germanus in Constantinople. Appointed bishop of Sourozh (modern Sudak in the Crimea) by Patriarch Germanus on the eve of the iconoclast persecution, he served his remote see — a key Greek-speaking outpost on the Black Sea coast — for over fifty years.
He refused to sign Emperor Leo III's iconoclast decrees of 730 and was tortured by the imperial authorities. He survived imprisonment and returned to Sourozh, where he continued his episcopate through the rest of the iconoclast era until the Triumph of Orthodoxy in 843.
He was particularly venerated in the medieval Russian Church because his see at Sourozh became, after the Christianization of the Rus', one of the principal Eastern bishoprics with a long Russian connection. The Life of Stephen of Sourozh is one of the major sources for early medieval Greek-Russian contact.